University of Wollongong
Browse

Thulium Oxide Nanoparticles: A new candidate for image-guided radiotherapy

Download (609.74 kB)
journal contribution
posted on 2024-11-16, 02:03 authored by Elette EngelsElette Engels, Matt Westlake, Nan Li, Sarah VogelSarah Vogel, Quentin Gobert, Nathan Thorpe, Anatoly RozenfeldAnatoly Rozenfeld, Michael LerchMichael Lerch, Stephanie Corde TeheiStephanie Corde Tehei, Moeava TeheiMoeava Tehei
Nanoparticles, with their distinct properties that vary from their bulk material equivalent, continue to gain popularity for studies into multi-modal applications in medicine. This research introduces the use of thulium oxide nanoparticles for biological applications and characterizes the potential of this novel nanoparticle for image-guided radiotherapy of brain cancer. In this study, we investigate the structural characteristics of this nanoparticle, and reveal a significant dose enhancement towards radioresistant brain tumour cells in vitro that also underlies an improvement in the CT image contrast of brain tumours in vivo. The thulium oxide nanoparticles utilized in the investigations described in this article were measured to be 40–45 nm from x-ray diffraction and scanning electron microscopy data. In vitro investigations assessed the cell survival and DNA damage in 9 l gliosarcoma cells following irradiation with 150 kVp orthovoltage x-rays. Immediately after the 150 kVp irradiation (15 min) an increase in the number of γ-H2AX induced foci indicates the production of more double-strand DNA breaks. Following from the short time-frame irradiation outcomes, clonogenic cell survival assays confirmed long-term radio-sensitization, with the cell sensitivity increasing by a factor of 1.32 (measured at the 10% survival fraction) for the irradiated 9 l cells exposed to thulium nanoparticles. A simple CT experiment shows that our thulium nanoparticles suspended in water at concentrations >0.5 mg ml−1 (0.05–20 mg ml−1 investigated) are clearly observable against water. Extending the CT experiment to an in vivo investigation, cellular uptake of the nanoparticles was demonstrated through CT image enhancement of the cancer site in 9- to 10-week-old Fisher rats bearing 9 l gliosarcomas, 12 days after cell implantation. The 9 l cancer is clearly visible on the CT image after injecting 40 μg of nanoparticles (2 μl at 20 mg ml−1) directly to the cancer site (5.5 mm from the dura and 3.5 mm right laterally of the bregma, 5 mm depth). To our knowledge, this work demonstrates the first application of thulium nanoparticles in biology and medicine, for radiotherapy and image guidance purposes.

Funding

X-RATE: A novel radiation detector platform to realize new opportunities in radiotherapy at the Australian Synchrotron

National Health and Medical Research Council

Find out more...

Design and application of new nanomaterials theranostic platforms for targeted treatment of cancer

National Health and Medical Research Council

Find out more...

History

Citation

Engels, E., Westlake, M., Li, N., Vogel, S., Gobert, Q., Thorpe, N., Rosenfeld, A., Lerch, M., Corde, S. & Tehei, M. (2018). Thulium Oxide Nanoparticles: A new candidate for image-guided radiotherapy. Biomedical Physics and Engineering Express, 4 (4), 044001-1-044001-11.

Journal title

Biomedical Physics and Engineering Express

Volume

4

Issue

4

Language

English

RIS ID

127999

Usage metrics

    Categories

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC